Abstract: A film production method for producing a layer containing a metal oxide, the film production method including: a heating step of heating a metal foil containing a first metal by bringing a part of the metal foil into contact with at least one heat generator; a first contact step of letting first gas containing a second metal to be in contact with both surfaces of the metal foil in a state where the part of the metal foil is supported; and a second contact step of letting second gas containing an oxidant to be in contact with the both surfaces of the metal foil in a state where the part of the metal foil is supported.

Abstract: An electrode foil for an electrolytic capacitor includes: a metal foil with a first main surface and a second main surface that is opposite to the first main surface, having a first porous portion on the first main surface side and a second porous portion on the second main surface side; a first dielectric layer that covers a surface of the first porous portion; and a second dielectric layer that covers a surface of the second porous portion. A thickness F1 of the first dielectric layer and a thickness F2 of the second dielectric layer satisfy the relationship 0.75?F1/F2?0.97.

Abstract: An electrode foil for an electrolytic capacitor includes: an anode body that contains a valve action metal; a first dielectric layer that covers at least a part of the anode body; and a second dielectric layer that covers at least a part of the first dielectric layer. The second dielectric layer has a higher dielectric constant than the first dielectric layer, and a thickness T2 of the second dielectric layer is greater than a thickness T1 of the first dielectric layer. The first dielectric layer is a layer that suppresses oxygen diffusion from the second dielectric layer to the anode body.

Abstract: A film production method for producing a layer containing a metal oxide, the film production method including: a heating step of heating a metal foil containing a first metal by bringing a part of the metal foil into contact with at least one heat generator; a first contact step of letting first gas containing a second metal to be in contact with both surfaces of the metal foil in a state where the part of the metal foil is supported; and a second contact step of letting second gas containing an oxidant to be in contact with the both surfaces of the metal foil in a state where the part of the metal foil is supported.

Abstract: An electrode foil for an electrolytic capacitor includes a metal foil having a porous part, and a dielectric layer covering a surface of a metal framework constituting the porous part. The dielectric layer includes a first layer containing an oxide of a second metal different from a first metal contained in the metal framework. The first layer has a thickness T1. The first layer contains at least one kind of additive element selected from the group consisting of carbon, phosphorus, boron, and nitrogen. The first layer includes a first region from an outer surface of the first layer to a center of the first layer in a thickness direction, and a second region from the center to an inner surface of the first layer. A content of the at least one kind of additive element in the first region is greater than a content of the at least one kind of additive element in the second region.

Abstract: An electrode foil for an electrolytic capacitor including a metal porous portion, and a metal core portion continuous to the metal porous portion. When the metal porous portion is equally divided in three in a thickness direction of the metal porous portion into a first region, a second region, and a third region sequentially from the metal core portion side, the first region has a porosity P1, the second region has a porosity P2, and the third region has a porosity P3, satisfying P1<P2<P3.

Abstract: An electrode foil for an electrolytic capacitor includes an anode electrode body including a base material part having a porous body portion, and a dielectric layer disposed on a surface of the porous body portion. The anode electrode body has a first main surface in which pores of the porous body portion are opened, a second main surface opposite to the first main surface, and an end surface connecting the first main surface and the second main surface. In the porous body portion, a first film thickness of the dielectric layer in an end surface vicinity region is larger than a second film thickness of the dielectric layer in a deep inner region, the end surface vicinity region being a region within a predetermined distance from the end surface, the deep inner region being a region located away from the first main surface and at a central portion in a direction parallel to the first main surface.

Abstract: An electrode foil for an electrolytic capacitor includes: an anode body including a first metal; a first dielectric layer covering at least a part of the anode body and including an oxide of the first metal; and a second dielectric layer covering at least a part of the first dielectric layer and including an oxide of a second metal. The first metal includes at least one selected from the group consisting of titanium, tantalum, niobium, and aluminum. And the second metal includes at least one selected from the group consisting of silicon, zirconium, hafnium, and tantalum. A thickness T2 of the second dielectric layer is smaller than a thickness T1 of the first dielectric layer.

Abstract: An electrode foil for an electrolytic capacitor includes an anode body foil having a porous part, and a dielectric layer covering a surface of a metal framework constituting the porous part. The dielectric layer includes a first layer containing an oxide of a second metal, the second metal being different from a first metal contained in the metal framework. An underlayer that is continuous with the first layer is provided between the metal framework and the first layer. The underlayer contains phosphorus and carbon.

Abstract: A film-forming device disclosed is a film-forming device for forming a film on a metal foil having a porous portion on a main surface thereof by a gas phase method, and includes a film-forming region in which the film is formed on the metal foil, conveyors to provided downstream of the film-forming region and drawing the metal foil from the film-forming region, and a control unit that controls the stress applied to the metal foil from the conveyors to 21 N/mm2 or less. This provides a film-forming device which does not cause defects easily on a film-forming target metal foil.

Abstract: An electrode foil for an electrolytic capacitor includes an anode body having a porous portion and a core part continuous with the porous portion, a dielectric layer covering a surface of a metal skeleton forming the porous portion, wherein an interface layer including a first element is present between the metal skeleton and the dielectric layer, and the first element is at least one selected from the group consisting of sulfur, nitrogen, and phosphorus.

Abstract: An electrode foil for an electrolytic capacitor includes a base material containing a valve metal and a dissimilar metal composite layer covering a surface of the base material. The dissimilar metal composite layer includes a mixed region in which a first metal and a second metal are mixed. The second metal is different from the first metal. The mixed region constitutes at least 50% of the dissimilar metal composite layer in a thickness-wise direction of the dissimilar metal composite layer. Each of a content M1 of the first metal and a content M2 of the second metal with respect to all metals in the mixed region is 1 atomic % or more.

Abstract: An electrode foil for an electrolytic capacitor includes: an anode body including a first metal; a first dielectric layer covering at least a part of the anode body and including an oxide of the first metal; and a second dielectric layer covering at least a part of the first dielectric layer and including an oxide of a second metal. The first metal includes at least one selected from the group consisting of titanium, tantalum, niobium, and aluminum. And the second metal includes at least one selected from the group consisting of silicon, zirconium, hafnium, and tantalum. A thickness T2 of the second dielectric layer is smaller than a thickness T1 of the first dielectric layer.

Abstract: A cathode foil for electrolytic capacitors includes a metal porous part, a metal core part that is continuous with the metal porous part, and a coating film covering the metal porous part. Pores in the metal porous part are open at a first main surface of the cathode foil. The coating film is disposed in a region from the first main surface to a depth more than or equal to 10% of a thickness of the metal porous part in a thickness direction of the metal porous part.

Abstract: An electrode foil for an electrolytic capacitor including a metal porous portion, and a metal core portion continuous to the metal porous portion. When the metal porous portion is equally divided in three in a thickness direction of the metal porous portion into a first region, a second region, and a third region sequentially from the metal core portion side, the first region has a porosity P1, the second region has a porosity P2, and the third region has a porosity P3, satisfying P1<P2<P3.

Abstract: A film production method for producing a layer containing a metal oxide, the film production method including: a heating step of heating a metal foil containing a first metal by bringing a part of the metal foil into contact with at least one heat generator; a first contact step of letting first gas containing a second metal to be in contact with both surfaces of the metal foil in a state where the part of the metal foil is supported; and a second contact step of letting second gas containing an oxidant to be in contact with the both surfaces of the metal foil in a state where the part of the metal foil is supported.

Abstract: An electrode includes a core portion including a first metal, and a porous portion disposed in contact with the core portion. The porous portion includes a porous body, a first dielectric layer, and a second dielectric layer. The porous body is integrated with the core portion and includes the first metal. The first dielectric layer covers at least a part of a surface of the porous body. And the second dielectric layer covers at least a part of the first dielectric layer. The first dielectric layer includes oxide of first metal, and the second dielectric layer includes oxide of a second metal. The second metal is different from the first metal. When T is a thickness of the porous portion, the second metal is distributed to a region closer to the core portion than a position of 0.5T from a boundary between the core portion and the porous portion.

Abstract: An electrode foil for an electrolytic capacitor includes a metal foil having a porous part, and a dielectric layer covering a surface of a metal framework constituting the porous part. The dielectric layer includes a first layer containing an oxide of a second metal different from a first metal contained in the metal framework. The first layer has a thickness T1. The first layer contains at least one kind of additive element selected from the group consisting of carbon, phosphorus, boron, and nitrogen. The first layer includes a first region from an outer surface of the first layer to a center of the first layer in a thickness direction, and a second region from the center to an inner surface of the first layer. A content of the at least one kind of additive element in the second region is greater than a content of the at least one kind of additive element in the first region.

Abstract: An electrode foil for an electrolytic capacitor includes an anode body foil having a porous part, and a dielectric layer covering a surface of a metal framework constituting the porous part. The dielectric layer includes a first layer containing an oxide of a second metal, the second metal being different from a first metal contained in the metal framework. An underlayer that is continuous with the first layer is provided between the metal framework and the first layer. The underlayer contains phosphorus and carbon.

Abstract: An electrode foil for an electrolytic capacitor includes an anode electrode body including a base material part having a porous body portion, and a dielectric layer disposed on a surface of the porous body portion. The anode electrode body has a first main surface in which pores of the porous body portion are opened, a second main surface opposite to the first main surface, and an end surface connecting the first main surface and the second main surface. In the porous body portion, a first film thickness of the dielectric layer in an end surface vicinity region is larger than a second film thickness of the dielectric layer in a deep inner region, the end surface vicinity region being a region within a predetermined distance from the end surface, the deep inner region being a region located away from the first main surface and at a central portion in a direction parallel to the first main surface.